1. The Field of the Invention
Exemplary embodiments of the present invention generally relate to apparatus, systems and methods for closing an opening in a body vessel of a human or animal. More particularly, embodiments of the present invention generally relate to devices for engaging tissue around an opening in a body vessel formed during a percutaneous medical procedure, and to systems and methods for using such devices.
2. The Relevant Technology
One element in any medical procedure is the control and stoppage of blood loss. Stopping blood loss is a particular concern in intravascular medical procedures where a laceration in a vein or artery is made to grant venous or arterial access. Such procedures may be diagnostic or therapeutic in nature, and commonly involve, for example, the insertion, use, and removal of a catheter or stent to diagnose or treat a medical condition. During the procedure, an introducer sheath may allow introduction of various devices into the vessel while also minimizing blood loss during the procedure. Upon completion of the procedure, however, the devices and the introducer may be removed, thereby leaving a laceration or puncture in the vessel wall.
This laceration or puncture site is of particular concern in controlling the patient's blood loss. If the site is left unsealed, blood may escape and enter into the surrounding body cavities and tissue. Where excessive blood escapes, the effectiveness of the medical procedure may be compromised and complications may arise. To avoid or counter these complications, the medical staff must be vigilant in providing continued care to the patient following an intravascular procedure.
One method used to avoid excessive bleeding is to apply pressure to the affected area. This process attempts to block flow from the body vessel until the natural clotting process is complete. Pressure may be manually applied, or with a sandbag, bandage, or clamp. Moreover, the effectiveness of this pressure is compromised unless the patient remains nearly motionless while the pressure is applied. Patients are monitored during the time during which clotting is occurring, thereby also requiring much of a physician's or nurse's time. Typically, this natural process takes up to two hours; however, with other patients even more time may be required. The need for the patient to be immobilized can cause discomfort to the patient. In addition, the time for hemostasis potentially increases both the time during which the medical staff must monitor the patient as well as the patient's hospital stay, thus adding to the expense of the procedure.
Additional devices and techniques have been suggested to reduce the amount of time for hemostasis by percutaneously sealing a vascular opening by plugging, suturing and/or mechanically closing the puncture site. For example, collagen plugs are well known in the art. The collagen plug may be deployed into the vascular opening through an introducer sheath. When deployed, the blood or other body fluids cause the collagen plug to swell, such that it blocks the access site and provides hemostasis. Such devices may, however, be difficult to properly position in the vessel. Consequently, an improperly deployed plug may block the flow of fluid in the vessel, and/or be released into the blood stream where it can float downstream and potentially embolize.
Other mechanical devices or methods have been suggested for closing a puncture site. By way of example, a staple may be used. In one configuration, an “S” shaped staple includes barbs that may engage tissue on either side of the wound. Another staple may be ring-shaped and include barbs that project from the ring. Sides of the ring can be squeezed to separate the barbs, while the barbs may engage the tissue on either side of the wound. The sides can then be released, causing the barbs to return closer together, thereby also pulling the tissue closed over the wound. These staples, however, have a large cross-sectional profile and may not be easy to deliver through a percutaneous access site to close an opening in a vessel wall.
Accordingly, there remains a need for a vascular closure device which promotes rapid hemostasis and which can be easily positioned and deployed into a small access site to close an opening or puncture in a bodily vessel.